Per- and polyfluoroalkyl substances: HFCs and HFOs a distinct subset
Per- and polyfluoroalkyl substances (“PFASs”) covers a broad range of substances that have in common that they contain at least one perfluoralkyl moiety . Some subsets of PFASs have very persistent and/or very bioaccumulative properties leading to classification or potential classification as Substances of Very High Concern. In contrast, the HFCs and HFOs are low boiling point substances, typically of low toxicity, that do not bio-accumulate and that breakdown down in days, months or years in the atmosphere. Some HFCs are used as propellants in Metered-Dose Inhalers (MDIs) for treatment of asthma and other respiratory conditions.
Recently the Inter-Organization Programme for the sound Management of Chemicals (IOMC) published an updated database of PFASs which includes “several new groups of PFASs that fulfil the common definition of PFASs (i.e. they contain at least one perfluoroalkyl moiety) but have not yet been commonly regarded as PFASs” The data base identifies both HFCs and HFOs as a group of substances that are covered by the definition.
EFCTC takes the view that any regulatory action should be at the subset or individual substance level and not at the PFAS group level and should be based on sound scientific evidence that takes into account specific structures and properties. Indeed, for HFCs and HFOs this seems to be recognized by IOMC which confirms that HFCs and HFOs have not been commonly regarded as PFASs.
 OECD Environment, Health and Safety Publications Series on Risk Management No. 39, 2018